diff --git a/src/test/fuzz/deserialize.cpp b/src/test/fuzz/deserialize.cpp
--- a/src/test/fuzz/deserialize.cpp
+++ b/src/test/fuzz/deserialize.cpp
@@ -179,8 +179,8 @@
         DeserializeFromFuzzingInput(buffer, s);
         AssertEqualAfterSerializeDeserialize(s);
 #elif MESSAGEHEADER_DESERIALIZE
-        const CMessageHeader::MessageMagic pchMessageStart = {0x00, 0x00, 0x00,
-                                                              0x00};
+        const CMessageHeader::MessageMagic pchMessageStart = {
+            {0x00, 0x00, 0x00, 0x00}};
         CMessageHeader mh(pchMessageStart);
         DeserializeFromFuzzingInput(buffer, mh);
         (void)mh.IsValidWithoutConfig(pchMessageStart);
diff --git a/src/test/fuzz/script.cpp b/src/test/fuzz/script.cpp
--- a/src/test/fuzz/script.cpp
+++ b/src/test/fuzz/script.cpp
@@ -49,7 +49,7 @@
     if (CompressScript(script, compressed)) {
         const unsigned int size = compressed[0];
         compressed.erase(compressed.begin());
-        assert(size >= 0 && size <= 5);
+        assert(size <= 5);
         CScript decompressed_script;
         const bool ok = DecompressScript(decompressed_script, size, compressed);
         assert(ok);
diff --git a/src/test/fuzz/scriptnum_ops.cpp b/src/test/fuzz/scriptnum_ops.cpp
--- a/src/test/fuzz/scriptnum_ops.cpp
+++ b/src/test/fuzz/scriptnum_ops.cpp
@@ -39,7 +39,7 @@
                 const int64_t i =
                     fuzzed_data_provider.ConsumeIntegral<int64_t>();
                 assert((script_num == i) != (script_num != i));
-                assert((script_num <= i) != script_num > i);
+                assert((script_num <= i) != (script_num > i));
                 assert((script_num >= i) != (script_num < i));
                 // Avoid signed integer overflow:
                 // script/script.h:264:93: runtime error: signed integer
diff --git a/src/test/fuzz/signature_checker.cpp b/src/test/fuzz/signature_checker.cpp
--- a/src/test/fuzz/signature_checker.cpp
+++ b/src/test/fuzz/signature_checker.cpp
@@ -25,17 +25,17 @@
     FuzzedSignatureChecker(FuzzedDataProvider &fuzzed_data_provider)
         : m_fuzzed_data_provider(fuzzed_data_provider) {}
 
-    virtual bool CheckSig(const std::vector<uint8_t> &scriptSig,
-                          const std::vector<uint8_t> &vchPubKey,
-                          const CScript &scriptCode, uint32_t flags) const {
+    bool CheckSig(const std::vector<uint8_t> &scriptSig,
+                  const std::vector<uint8_t> &vchPubKey,
+                  const CScript &scriptCode, uint32_t flags) const override {
         return m_fuzzed_data_provider.ConsumeBool();
     }
 
-    virtual bool CheckLockTime(const CScriptNum &nLockTime) const {
+    bool CheckLockTime(const CScriptNum &nLockTime) const override {
         return m_fuzzed_data_provider.ConsumeBool();
     }
 
-    virtual bool CheckSequence(const CScriptNum &nSequence) const {
+    bool CheckSequence(const CScriptNum &nSequence) const override {
         return m_fuzzed_data_provider.ConsumeBool();
     }